The present invention is a development of a joint prosthesis of the kind disclosed in U.S. Pat. No. 5,037,439, to Albrektsson et al. This document thus inter alia discloses a femoral part of a knee joint prosthesis comprising an articulation element having an inner surface in the shape of an L. This L-shaped articulation element comprises two essentially planar parts oriented perpendicularly to each other intended to be connected to a L-shaped recess cut in the femur bone tissue. The prosthesis also comprises an elongate intermediate element with a first side intended to bear against the vertical part of the L-shaped recess in the bone by means of at least one fixture, and a second opposite side intended to bear against one of the planar parts of the articulation element. The intermediate element is in the shape of an attachment bar having flanges provided on said second side intended as a means for holding the articulation element. The back part of the articulation element is also provided with an elongated means for attachment, having a T-shaped cross section area, intended to be inserted in said attachment bar and be locked in a predetermined position by a locking device which consists of locking lugs in the flanges of the intermediate element.
This prior art discloses a femoral part of a knee joint prosthesis which can be fitted in one operation only, which is advantageous since two operations may entail a greater risk of infection and are troublesome for the patient.
The present invention is an improvement of the prosthesis described above. Due to its shape it has a large area for osseointegration resulting in a good osseointegration in the bone tissue and thus a stable and resistant anchoring in the femur. The parts of the prosthesis all have a relatively simple construction and are easy to fit during one operation. The fitting of the articulation element to the attachment part is also simple and stable.
Other similar prior art is disclosed for instance in EP 0 183 669.